Radionuclides from uranium and thorium series were analyzed to evaluate the radiological quality of the released wastewater from a uranium mine under decommissioning process. The results based on Pearson's R² analysis showed that the activity concentration of radionuclides in soluble and particulate fractions were statistically independent. The wastewater poses no radiological impacts to surrounding waters, generating maximum dose rates of 65 µSv·y⁻¹. Cancer risk was analyzed, and the value found is below that suggested to undertake some actions. Among the radionuclides studied, ²¹⁰Pb and ²²⁸Ra were the major contributors to both dose rate and cancer risk.